1915.] Matthew and Granger, Lower Eocene Wasatch and Wind River Faunas. sO 
To this species I provisionally refer two specimens from the Gray Bull 
beds (Nos. 15324 and 15325), the former a jaw fragment with molars, the 
latter a fragment of palate and jaw with upper and lower molars. The 
lower molars are about equal to those of the type in size and the upper molars 
show antero-posterior compression. Since the characters of the species are 
principally in the premolars, this reference to LE. he eee is made with 
uncertainty. . : 
Measurements, in millimeters, of upper molars, No. 15325, from the Gray 
Bull beds::m*amty pest.=6;, mr tr = 10,53, o> =.21.52 an wait: post) = 7.8: 
a igs. 
Ectocion ralstonensis sp. nov. 
Type, No. 16050, lower jaw with ps3-me2 and roots of c—pe, left side; 
Clark Fork beds, Head of Big Sand Cas Clark Fork basin, Wyo. Exp. 
1912. 
Paratypes, No. 16049, lower jaw with p4-ms, and No. 15853, m'°, left 
side; both from same locality 
and horizon as type. 
Specific Characters. P3-m3 = 
2.4, Wiese = 10.0 Be Ne cpa OF 
about equal length; anterior 
part of jaw shallow, and sym- | 3 . 
. Fig. 14. Ectocion ralstonensis, lower jaw, ex- 
physeal region slender; ento- ternal view. Type, Clark Fork beds, Clark Fork 
conid on pa relatively weak. basin, Wyoming. ‘ 
Distinguished from kL. os- 
bornianum by smaller size and_ relative. siuiieaises and slenderness of 
ramus. The upper molars do not show the antero-posterior compression 
seen in some specimens referred to LH. osbornianum from. the same horizon. 
The species is abundant in the Clark Fork beds, fairly so in the Sand 
Coulee beds, while from the Gray Bull I refer several specimens, most of 
which average a little larger than the type. 
Two maxilla from the Sand Coulee beds show the p®, and in both fhe 
protocone is placed posteriorly against the p*. Supplementary measure- 
ments from No. 16124 are: p*®-m® = 29.5, p* ant. post. diam. = 5.8, p* 
tr. diam. = 7.4. 
Ectocion parvus sp. nov. 
Type, No. 16080, a lower jaw fragment with m1-s, left side; Clark Fork 
beds, Head of Big Sand Coulee, Clark Fork basin, Wyo. Exp. 1911. 
Distinctive Characters. My-3 = 16.2, first and last molar of equal length. 
